hi everyone. i need some advice...

im 6 weeks pg this wednesday, but ive just started bleeding. its not very heavy but its more than i would like to see (sorry for TMI) i also have cramps in my lower abdomin that come and go and can sometimes be quite bad i cant help but be really scared as much as i try to think positive. i need to go to the doctors and have U/S and all that but im only 19 and its really something i cant afford until pay day. whats do you all think it might be?